Vulnerability Database

383,304

Total vulnerabilities in the database

CVE-2021-1620 — cisco / ios

Missing Release of Resource after Effective Lifetime

A vulnerability in the Internet Key Exchange Version 2 (IKEv2) support for the AutoReconnect feature of Cisco IOS Software and Cisco IOS XE Software could allow an authenticated, remote attacker to exhaust the free IP addresses from the assigned local pool. This vulnerability occurs because the code does not release the allocated IP address under certain failure conditions. An attacker could exploit this vulnerability by trying to connect to the device with a non-AnyConnect client. A successful exploit could allow the attacker to exhaust the IP addresses from the assigned local pool, which prevents users from logging in and leads to a denial of service (DoS) condition.

  • Published: Sep 23, 2021
  • Updated: Sep 13, 2026
  • CVE: CVE-2021-1620
  • Severity: High
  • Exploit:
  • CISA KEV:

CVSS v3:

  • Severity: High
  • Score: 7.7
  • AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H

CVSS v2:

  • Severity: Low
  • Score: 3.5
  • AV:N/AC:M/Au:S/C:N/I:N/A:P
Software Affected versions
cisco / ios = 12.2(6)i1
cisco / ios = 15.1(3)svr1
cisco / ios = 15.1(3)svr2
cisco / ios = 15.1(3)svr3
cisco / ios = 15.1(3)svs
cisco / ios = 15.1(3)svs1
cisco / ios = 15.1(3)svt1
cisco / ios = 15.1(3)svt2
cisco / ios = 15.1(3)svu1
cisco / ios = 15.2(1)sy2
cisco / ios = 15.2(1)sy3
cisco / ios = 15.2(1)sy4
cisco / ios = 15.2(1)sy5
cisco / ios = 15.2(1)sy6
cisco / ios = 15.2(1)sy7
cisco / ios = 15.2(1)sy8
cisco / ios = 15.2(4)e
cisco / ios = 15.2(4)e1
cisco / ios = 15.2(4)e2
cisco / ios = 15.2(4)e3
cisco / ios = 15.2(4)e4
cisco / ios = 15.2(4)e5
cisco / ios = 15.2(4)e5a
cisco / ios = 15.2(4)e6
cisco / ios = 15.2(4)e7
cisco / ios = 15.2(4)e8
cisco / ios = 15.2(4)e9
cisco / ios = 15.2(4)e10
cisco / ios = 15.2(4)e10a
cisco / ios = 15.2(4)e10b
cisco / ios = 15.2(4)ea
cisco / ios = 15.2(4)ea1
cisco / ios = 15.2(4)ea2
cisco / ios = 15.2(4)ea3
cisco / ios = 15.2(4)ea4
cisco / ios = 15.2(4)ea5
cisco / ios = 15.2(4)ea6
cisco / ios = 15.2(4)ea7
cisco / ios = 15.2(4)ea8
cisco / ios = 15.2(4)ea9
cisco / ios = 15.2(4)ea9a
cisco / ios = 15.2(4)ec1
cisco / ios = 15.2(4)ec2
cisco / ios = 15.2(4m)e1
cisco / ios = 15.2(4m)e2
cisco / ios = 15.2(4m)e3
cisco / ios = 15.2(4n)e2
cisco / ios = 15.2(4o)e2
cisco / ios = 15.2(4o)e3
cisco / ios = 15.2(4p)e1
cisco / ios = 15.2(4q)e1
cisco / ios = 15.2(4s)e1
cisco / ios = 15.2(5)e
cisco / ios = 15.2(5)e1
cisco / ios = 15.2(5)e2
cisco / ios = 15.2(5)e2b
cisco / ios = 15.2(5)e2c
cisco / ios = 15.2(5)ea
cisco / ios = 15.2(5)ex
cisco / ios = 15.2(5a)e
cisco / ios = 15.2(5a)e1
cisco / ios = 15.2(5b)e
cisco / ios = 15.2(5c)e
cisco / ios = 15.2(6)e
cisco / ios = 15.2(6)e0a
cisco / ios = 15.2(6)e0c
cisco / ios = 15.2(6)e1
cisco / ios = 15.2(6)e1a
cisco / ios = 15.2(6)e1s
cisco / ios = 15.2(6)e2
cisco / ios = 15.2(6)e2a
cisco / ios = 15.2(6)e2b
cisco / ios = 15.2(6)e3
cisco / ios = 15.2(6)eb
cisco / ios = 15.2(7)e
cisco / ios = 15.2(7)e0a
cisco / ios = 15.2(7)e0b
cisco / ios = 15.2(7)e0s
cisco / ios = 15.2(7)e1
cisco / ios = 15.2(7)e1a
cisco / ios = 15.2(7)e2
cisco / ios = 15.2(7)e2a
cisco / ios = 15.2(7)e2b
cisco / ios = 15.2(7)e3
cisco / ios = 15.2(7)e3a
cisco / ios = 15.2(7)e3k
cisco / ios = 15.2(7)e4
cisco / ios = 15.2(7)e5
cisco / ios = 15.2(7)e99
cisco / ios = 15.2(7a)e0b
cisco / ios = 15.2(7b)e0b
cisco / ios = 15.2(8)e
cisco / ios = 15.2(8)e1
cisco / ios = 15.2(234k)e
cisco / ios = 15.3(0)sy
cisco / ios = 15.3(1)sy
cisco / ios = 15.3(1)sy1
cisco / ios = 15.3(1)sy2
cisco / ios = 15.3(3)jc6
cisco / ios = 15.3(3)jc8
cisco / ios = 15.3(3)jc9
cisco / ios = 15.3(3)jc14
cisco / ios = 15.3(3)jca7
cisco / ios = 15.3(3)jca8
cisco / ios = 15.3(3)jca9
cisco / ios = 15.3(3)jd3
cisco / ios = 15.3(3)jd4
cisco / ios = 15.3(3)jd5
cisco / ios = 15.3(3)jd6
cisco / ios = 15.3(3)jd7
cisco / ios = 15.3(3)jd8
cisco / ios = 15.3(3)jd9
cisco / ios = 15.3(3)jd11
cisco / ios = 15.3(3)jd12
cisco / ios = 15.3(3)jd13
cisco / ios = 15.3(3)jd14
cisco / ios = 15.3(3)jd16
cisco / ios = 15.3(3)jd17
cisco / ios = 15.3(3)jda7
cisco / ios = 15.3(3)jda8
cisco / ios = 15.3(3)jda9
cisco / ios = 15.3(3)jda11
cisco / ios = 15.3(3)jda12
cisco / ios = 15.3(3)jda13
cisco / ios = 15.3(3)jda14
cisco / ios = 15.3(3)jda16
cisco / ios = 15.3(3)jda17
cisco / ios = 15.3(3)je
cisco / ios = 15.3(3)jf
cisco / ios = 15.3(3)jf1
cisco / ios = 15.3(3)jf2
cisco / ios = 15.3(3)jf4
cisco / ios = 15.3(3)jf5
cisco / ios = 15.3(3)jf6
cisco / ios = 15.3(3)jf7
cisco / ios = 15.3(3)jf8
cisco / ios = 15.3(3)jf9
cisco / ios = 15.3(3)jf10
cisco / ios = 15.3(3)jf11
cisco / ios = 15.3(3)jf12
cisco / ios = 15.3(3)jf12i
cisco / ios = 15.3(3)jf14
cisco / ios = 15.3(3)jf14i
cisco / ios = 15.3(3)jf15
cisco / ios = 15.3(3)jg
cisco / ios = 15.3(3)jg1
cisco / ios = 15.3(3)jh
cisco / ios = 15.3(3)jh1
cisco / ios = 15.3(3)ji1
cisco / ios = 15.3(3)ji3
cisco / ios = 15.3(3)ji4
cisco / ios = 15.3(3)ji5
cisco / ios = 15.3(3)ji6
cisco / ios = 15.3(3)jj
cisco / ios = 15.3(3)jj1
cisco / ios = 15.3(3)jk
cisco / ios = 15.3(3)jk1
cisco / ios = 15.3(3)jk1t
cisco / ios = 15.3(3)jk2
cisco / ios = 15.3(3)jk2a
cisco / ios = 15.3(3)jk3
cisco / ios = 15.3(3)jk4
cisco / ios = 15.3(3)jk5
cisco / ios = 15.3(3)jk6
cisco / ios = 15.3(3)jk100
cisco / ios = 15.3(3)jn13
cisco / ios = 15.3(3)jn14
cisco / ios = 15.3(3)jn15
cisco / ios = 15.3(3)jpc5
cisco / ios = 15.3(3)jpi1
cisco / ios = 15.3(3)jpi1t
cisco / ios = 15.3(3)jpi4
cisco / ios = 15.3(3)jpi5
cisco / ios = 15.3(3)jpi5s
cisco / ios = 15.3(3)jpi6a
cisco / ios = 15.3(3)jpi7
cisco / ios = 15.3(3)jpi8
cisco / ios = 15.3(3)jpj2
cisco / ios = 15.3(3)jpj2t
cisco / ios = 15.3(3)jpj3
cisco / ios = 15.3(3)jpj3a
cisco / ios = 15.3(3)jpj4
cisco / ios = 15.3(3)jpj5
cisco / ios = 15.3(3)jpj6
cisco / ios = 15.3(3)jpj7
cisco / ios = 15.3(3)jpk
cisco / ios = 15.3(3)jpk1
cisco / ios = 15.3(3)jpk2
cisco / ios = 15.4(1)cg
cisco / ios = 15.4(1)cg1
cisco / ios = 15.4(1)s
cisco / ios = 15.4(1)s1
cisco / ios = 15.4(1)s2
cisco / ios = 15.4(1)s3
cisco / ios = 15.4(1)s4
cisco / ios = 15.4(1)sy
cisco / ios = 15.4(1)sy1
cisco / ios = 15.4(1)sy2
cisco / ios = 15.4(1)sy3
cisco / ios = 15.4(1)sy4
cisco / ios = 15.4(1)t
cisco / ios = 15.4(1)t1
cisco / ios = 15.4(1)t2
cisco / ios = 15.4(1)t3
cisco / ios = 15.4(1)t4
cisco / ios = 15.4(2)cg
cisco / ios = 15.4(2)s
cisco / ios = 15.4(2)s1
cisco / ios = 15.4(2)s2
cisco / ios = 15.4(2)s3
cisco / ios = 15.4(2)s4
cisco / ios = 15.4(2)sn
cisco / ios = 15.4(2)sn1
cisco / ios = 15.4(2)t
cisco / ios = 15.4(2)t1
cisco / ios = 15.4(2)t2
cisco / ios = 15.4(2)t3
cisco / ios = 15.4(2)t4
cisco / ios = 15.4(3)m
cisco / ios = 15.4(3)m1
cisco / ios = 15.4(3)m2
cisco / ios = 15.4(3)m3
cisco / ios = 15.4(3)m4
cisco / ios = 15.4(3)m5
cisco / ios = 15.4(3)m6
cisco / ios = 15.4(3)m6a
cisco / ios = 15.4(3)m7
cisco / ios = 15.4(3)m7a
cisco / ios = 15.4(3)m8
cisco / ios = 15.4(3)m9
cisco / ios = 15.4(3)m10
cisco / ios = 15.4(3)s
cisco / ios = 15.4(3)s0d
cisco / ios = 15.4(3)s0e
cisco / ios = 15.4(3)s0f
cisco / ios = 15.4(3)s1
cisco / ios = 15.4(3)s2
cisco / ios = 15.4(3)s3
cisco / ios = 15.4(3)s4
cisco / ios = 15.4(3)s5
cisco / ios = 15.4(3)s6
cisco / ios = 15.4(3)s6a
cisco / ios = 15.4(3)s7
cisco / ios = 15.4(3)s8
cisco / ios = 15.4(3)s9
cisco / ios = 15.4(3)s10
cisco / ios = 15.4(3)sn1
cisco / ios = 15.4(3)sn1a
cisco / ios = 15.5(1)s
cisco / ios = 15.5(1)s1
cisco / ios = 15.5(1)s2
cisco / ios = 15.5(1)s3
cisco / ios = 15.5(1)s4
cisco / ios = 15.5(1)sn
cisco / ios = 15.5(1)sn1
cisco / ios = 15.5(1)sy
cisco / ios = 15.5(1)sy1
cisco / ios = 15.5(1)sy2
cisco / ios = 15.5(1)sy3
cisco / ios = 15.5(1)sy4
cisco / ios = 15.5(1)sy5
cisco / ios = 15.5(1)sy6
cisco / ios = 15.5(1)sy7
cisco / ios = 15.5(1)sy8
cisco / ios = 15.5(1)t
cisco / ios = 15.5(1)t1
cisco / ios = 15.5(1)t2
cisco / ios = 15.5(1)t3
cisco / ios = 15.5(1)t4
cisco / ios = 15.5(2)s
cisco / ios = 15.5(2)s1
cisco / ios = 15.5(2)s2
cisco / ios = 15.5(2)s3
cisco / ios = 15.5(2)s4
cisco / ios = 15.5(2)sn
cisco / ios = 15.5(2)t
cisco / ios = 15.5(2)t1
cisco / ios = 15.5(2)t2
cisco / ios = 15.5(2)t3
cisco / ios = 15.5(2)t4
cisco / ios = 15.5(2)xb
cisco / ios = 15.5(3)m
cisco / ios = 15.5(3)m0a
cisco / ios = 15.5(3)m1
cisco / ios = 15.5(3)m2
cisco / ios = 15.5(3)m2a
cisco / ios = 15.5(3)m3
cisco / ios = 15.5(3)m4
cisco / ios = 15.5(3)m4a
cisco / ios = 15.5(3)m4b
cisco / ios = 15.5(3)m4c
cisco / ios = 15.5(3)m5
cisco / ios = 15.5(3)m6
cisco / ios = 15.5(3)m6a
cisco / ios = 15.5(3)m7
cisco / ios = 15.5(3)m8
cisco / ios = 15.5(3)m9
cisco / ios = 15.5(3)m10
cisco / ios = 15.5(3)m11
cisco / ios = 15.5(3)m11a
cisco / ios = 15.5(3)s
cisco / ios = 15.5(3)s0a
cisco / ios = 15.5(3)s1
cisco / ios = 15.5(3)s1a
cisco / ios = 15.5(3)s2
cisco / ios = 15.5(3)s3
cisco / ios = 15.5(3)s4
cisco / ios = 15.5(3)s5
cisco / ios = 15.5(3)s6
cisco / ios = 15.5(3)s6a
cisco / ios = 15.5(3)s6b
cisco / ios = 15.5(3)s7
cisco / ios = 15.5(3)s8
cisco / ios = 15.5(3)s9
cisco / ios = 15.5(3)s9a
cisco / ios = 15.5(3)s10
cisco / ios = 15.5(3)s10a
cisco / ios = 15.5(3)s10b
cisco / ios = 15.5(3)sn
cisco / ios = 15.5(3)sn0a
cisco / ios = 15.6(1)s
cisco / ios = 15.6(1)s1
cisco / ios = 15.6(1)s2
cisco / ios = 15.6(1)s3
cisco / ios = 15.6(1)s4
cisco / ios = 15.6(1)sn
cisco / ios = 15.6(1)sn1
cisco / ios = 15.6(1)sn2
cisco / ios = 15.6(1)sn3
cisco / ios = 15.6(1)t
cisco / ios = 15.6(1)t0a
cisco / ios = 15.6(1)t1
cisco / ios = 15.6(1)t2
cisco / ios = 15.6(1)t3
cisco / ios = 15.6(2)s
cisco / ios = 15.6(2)s1
cisco / ios = 15.6(2)s2
cisco / ios = 15.6(2)s3
cisco / ios = 15.6(2)s4
cisco / ios = 15.6(2)sn
cisco / ios = 15.6(2)sp
cisco / ios = 15.6(2)sp1
cisco / ios = 15.6(2)sp2
cisco / ios = 15.6(2)sp3
cisco / ios = 15.6(2)sp4
cisco / ios = 15.6(2)sp5
cisco / ios = 15.6(2)sp6
cisco / ios = 15.6(2)sp7
cisco / ios = 15.6(2)sp8
cisco / ios = 15.6(2)sp8a
cisco / ios = 15.6(2)sp9
cisco / ios = 15.6(2)t
cisco / ios = 15.6(2)t0a
cisco / ios = 15.6(2)t1
cisco / ios = 15.6(2)t2
cisco / ios = 15.6(2)t3
cisco / ios = 15.6(3)m
cisco / ios = 15.6(3)m0a
cisco / ios = 15.6(3)m1
cisco / ios = 15.6(3)m1a
cisco / ios = 15.6(3)m1b
cisco / ios = 15.6(3)m2
cisco / ios = 15.6(3)m2a
cisco / ios = 15.6(3)m3
cisco / ios = 15.6(3)m3a
cisco / ios = 15.6(3)m4
cisco / ios = 15.6(3)m5
cisco / ios = 15.6(3)m6
cisco / ios = 15.6(3)m6a
cisco / ios = 15.6(3)m6b
cisco / ios = 15.6(3)m7
cisco / ios = 15.6(3)m8
cisco / ios = 15.6(3)m9
cisco / ios = 15.6(3)sn
cisco / ios = 15.6(4)sn
cisco / ios = 15.6(5)sn
cisco / ios = 15.6(7)sn
cisco / ios = 15.6(7)sn1
cisco / ios = 15.6(7)sn2
cisco / ios = 15.7(3)m
cisco / ios = 15.7(3)m0a
cisco / ios = 15.7(3)m1
cisco / ios = 15.7(3)m2
cisco / ios = 15.7(3)m3
cisco / ios = 15.7(3)m4
cisco / ios = 15.7(3)m4a
cisco / ios = 15.7(3)m4b
cisco / ios = 15.7(3)m5
cisco / ios = 15.7(3)m6
cisco / ios = 15.7(3)m7
cisco / ios = 15.7(3)m8
cisco / ios = 15.8(3)m
cisco / ios = 15.8(3)m0a
cisco / ios = 15.8(3)m0b
cisco / ios = 15.8(3)m1
cisco / ios = 15.8(3)m1a
cisco / ios = 15.8(3)m2
cisco / ios = 15.8(3)m2a
cisco / ios = 15.8(3)m3
cisco / ios = 15.8(3)m3a
cisco / ios = 15.8(3)m3b
cisco / ios = 15.8(3)m4
cisco / ios = 15.8(3)m5
cisco / ios = 15.8(3)m6
cisco / ios = 15.9(3)m
cisco / ios = 15.9(3)m0a
cisco / ios = 15.9(3)m1
cisco / ios = 15.9(3)m2
cisco / ios = 15.9(3)m2a
cisco / ios = 15.9(3)m3
cisco / ios = 15.9(3)m3a
cisco / ios = 15.9(3)m3b
cisco / ios_xe = 3.8.0e
cisco / ios_xe = 3.8.1e
cisco / ios_xe = 3.8.2e
cisco / ios_xe = 3.8.3e
cisco / ios_xe = 3.8.4e
cisco / ios_xe = 3.8.5ae
cisco / ios_xe = 3.8.5e
cisco / ios_xe = 3.8.6e
cisco / ios_xe = 3.8.7e
cisco / ios_xe = 3.8.8e
cisco / ios_xe = 3.8.9e
cisco / ios_xe = 3.8.10e
cisco / ios_xe = 3.9.0e
cisco / ios_xe = 3.9.1e
cisco / ios_xe = 3.9.2be
cisco / ios_xe = 3.9.2e
cisco / ios_xe = 3.10.0ce
cisco / ios_xe = 3.10.0e
cisco / ios_xe = 3.10.1ae
cisco / ios_xe = 3.10.1e
cisco / ios_xe = 3.10.1se
cisco / ios_xe = 3.10.2e
cisco / ios_xe = 3.10.3e
cisco / ios_xe = 3.11.0e
cisco / ios_xe = 3.11.0s
cisco / ios_xe = 3.11.1ae
cisco / ios_xe = 3.11.1e
cisco / ios_xe = 3.11.1s
cisco / ios_xe = 3.11.2ae
cisco / ios_xe = 3.11.2e
cisco / ios_xe = 3.11.2s
cisco / ios_xe = 3.11.3ae
cisco / ios_xe = 3.11.3e
cisco / ios_xe = 3.11.3s
cisco / ios_xe = 3.11.4e
cisco / ios_xe = 3.11.4s
cisco / ios_xe = 3.11.5e
cisco / ios_xe = 3.11.99ze
cisco / ios_xe = 3.12.0as
cisco / ios_xe = 3.12.0s
cisco / ios_xe = 3.12.1s
cisco / ios_xe = 3.12.2s
cisco / ios_xe = 3.12.3s
cisco / ios_xe = 3.12.4s
cisco / ios_xe = 3.13.0as
cisco / ios_xe = 3.13.0s
cisco / ios_xe = 3.13.1s
cisco / ios_xe = 3.13.2as
cisco / ios_xe = 3.13.2s
cisco / ios_xe = 3.13.3s
cisco / ios_xe = 3.13.4s
cisco / ios_xe = 3.13.5as
cisco / ios_xe = 3.13.5s
cisco / ios_xe = 3.13.6as
cisco / ios_xe = 3.13.6bs
cisco / ios_xe = 3.13.6s
cisco / ios_xe = 3.13.7as
cisco / ios_xe = 3.13.7s
cisco / ios_xe = 3.13.8s
cisco / ios_xe = 3.13.9s
cisco / ios_xe = 3.13.10s
cisco / ios_xe = 3.14.0s
cisco / ios_xe = 3.14.1s
cisco / ios_xe = 3.14.2s
cisco / ios_xe = 3.14.3s
cisco / ios_xe = 3.14.4s
cisco / ios_xe = 3.15.0s
cisco / ios_xe = 3.15.1cs
cisco / ios_xe = 3.15.1s
cisco / ios_xe = 3.15.1xbs
cisco / ios_xe = 3.15.2s
cisco / ios_xe = 3.15.2xbs
cisco / ios_xe = 3.15.3s
cisco / ios_xe = 3.15.4s
cisco / ios_xe = 3.16.0as
cisco / ios_xe = 3.16.0bs
cisco / ios_xe = 3.16.0cs
cisco / ios_xe = 3.16.0s
cisco / ios_xe = 3.16.1as
cisco / ios_xe = 3.16.1s
cisco / ios_xe = 3.16.2as
cisco / ios_xe = 3.16.2bs
cisco / ios_xe = 3.16.2s
cisco / ios_xe = 3.16.3as
cisco / ios_xe = 3.16.3s
cisco / ios_xe = 3.16.4as
cisco / ios_xe = 3.16.4bs
cisco / ios_xe = 3.16.4cs
cisco / ios_xe = 3.16.4ds
cisco / ios_xe = 3.16.4es
cisco / ios_xe = 3.16.4gs
cisco / ios_xe = 3.16.4s
cisco / ios_xe = 3.16.5as
cisco / ios_xe = 3.16.5bs
cisco / ios_xe = 3.16.5s
cisco / ios_xe = 3.16.6bs
cisco / ios_xe = 3.16.6s
cisco / ios_xe = 3.16.7as
cisco / ios_xe = 3.16.7bs
cisco / ios_xe = 3.16.7s
cisco / ios_xe = 3.16.8s
cisco / ios_xe = 3.16.9s
cisco / ios_xe = 3.16.10as
cisco / ios_xe = 3.16.10bs
cisco / ios_xe = 3.16.10s
cisco / ios_xe = 3.17.0s
cisco / ios_xe = 3.17.1as
cisco / ios_xe = 3.17.1s
cisco / ios_xe = 3.17.2s
cisco / ios_xe = 3.17.3s
cisco / ios_xe = 3.17.4s
cisco / ios_xe = 3.18.0as
cisco / ios_xe = 3.18.0s
cisco / ios_xe = 3.18.0sp
cisco / ios_xe = 3.18.1asp
cisco / ios_xe = 3.18.1bsp
cisco / ios_xe = 3.18.1csp
cisco / ios_xe = 3.18.1gsp
cisco / ios_xe = 3.18.1hsp
cisco / ios_xe = 3.18.1isp
cisco / ios_xe = 3.18.1s
cisco / ios_xe = 3.18.1sp
cisco / ios_xe = 3.18.2asp
cisco / ios_xe = 3.18.2s
cisco / ios_xe = 3.18.2sp
cisco / ios_xe = 3.18.3asp
cisco / ios_xe = 3.18.3bsp
cisco / ios_xe = 3.18.3s
cisco / ios_xe = 3.18.3sp
cisco / ios_xe = 3.18.4s
cisco / ios_xe = 3.18.4sp
cisco / ios_xe = 3.18.5sp
cisco / ios_xe = 3.18.6sp
cisco / ios_xe = 3.18.7sp
cisco / ios_xe = 3.18.8asp
cisco / ios_xe = 3.18.8sp
cisco / ios_xe = 3.18.9sp
cisco / ios_xe = 16.1.1
cisco / ios_xe = 16.1.2
cisco / ios_xe = 16.1.3
cisco / ios_xe = 16.2.1
cisco / ios_xe = 16.2.2
cisco / ios_xe = 16.3.1
cisco / ios_xe = 16.3.1a
cisco / ios_xe = 16.3.2
cisco / ios_xe = 16.3.3
cisco / ios_xe = 16.3.4
cisco / ios_xe = 16.3.5
cisco / ios_xe = 16.3.5b
cisco / ios_xe = 16.3.6
cisco / ios_xe = 16.3.7
cisco / ios_xe = 16.3.8
cisco / ios_xe = 16.3.9
cisco / ios_xe = 16.3.10
cisco / ios_xe = 16.3.11
cisco / ios_xe = 16.4.1
cisco / ios_xe = 16.4.2
cisco / ios_xe = 16.4.3
cisco / ios_xe = 16.5.1
cisco / ios_xe = 16.5.1a
cisco / ios_xe = 16.5.1b
cisco / ios_xe = 16.5.2
cisco / ios_xe = 16.5.3
cisco / ios_xe = 16.6.1
cisco / ios_xe = 16.6.2
cisco / ios_xe = 16.6.3
cisco / ios_xe = 16.6.4
cisco / ios_xe = 16.6.4a
cisco / ios_xe = 16.6.4s
cisco / ios_xe = 16.6.5
cisco / ios_xe = 16.6.5a
cisco / ios_xe = 16.6.5b
cisco / ios_xe = 16.6.6
cisco / ios_xe = 16.6.7
cisco / ios_xe = 16.6.7a
cisco / ios_xe = 16.6.8
cisco / ios_xe = 16.6.9
cisco / ios_xe = 16.7.1
cisco / ios_xe = 16.7.1a
cisco / ios_xe = 16.7.1b
cisco / ios_xe = 16.7.2
cisco / ios_xe = 16.7.3
cisco / ios_xe = 16.7.4
cisco / ios_xe = 16.8.1
cisco / ios_xe = 16.8.1a
cisco / ios_xe = 16.8.1b
cisco / ios_xe = 16.8.1c
cisco / ios_xe = 16.8.1d
cisco / ios_xe = 16.8.1e
cisco / ios_xe = 16.8.1s
cisco / ios_xe = 16.8.2
cisco / ios_xe = 16.8.3
cisco / ios_xe = 16.9.1
cisco / ios_xe = 16.9.1a
cisco / ios_xe = 16.9.1b
cisco / ios_xe = 16.9.1c
cisco / ios_xe = 16.9.1d
cisco / ios_xe = 16.9.1s
cisco / ios_xe = 16.9.2
cisco / ios_xe = 16.9.2a
cisco / ios_xe = 16.9.2s
cisco / ios_xe = 16.9.3
cisco / ios_xe = 16.9.3a
cisco / ios_xe = 16.9.3h
cisco / ios_xe = 16.9.3s
cisco / ios_xe = 16.9.4
cisco / ios_xe = 16.9.4c
cisco / ios_xe = 16.9.5
cisco / ios_xe = 16.9.5f
cisco / ios_xe = 16.9.6
cisco / ios_xe = 16.9.7
cisco / ios_xe = 16.10.1
cisco / ios_xe = 16.10.1a
cisco / ios_xe = 16.10.1b
cisco / ios_xe = 16.10.1c
cisco / ios_xe = 16.10.1d
cisco / ios_xe = 16.10.1e
cisco / ios_xe = 16.10.1f
cisco / ios_xe = 16.10.1g
cisco / ios_xe = 16.10.1s
cisco / ios_xe = 16.10.2
cisco / ios_xe = 16.10.3
cisco / ios_xe = 16.11.1
cisco / ios_xe = 16.11.1a
cisco / ios_xe = 16.11.1b
cisco / ios_xe = 16.11.1c
cisco / ios_xe = 16.11.1s
cisco / ios_xe = 16.11.2
cisco / ios_xe = 16.12.1
cisco / ios_xe = 16.12.1a
cisco / ios_xe = 16.12.1c
cisco / ios_xe = 16.12.1s
cisco / ios_xe = 16.12.1t
cisco / ios_xe = 16.12.1w
cisco / ios_xe = 16.12.1x
cisco / ios_xe = 16.12.1y
cisco / ios_xe = 16.12.1z
cisco / ios_xe = 16.12.1z1
cisco / ios_xe = 16.12.1z2
cisco / ios_xe = 16.12.1za
cisco / ios_xe = 16.12.2
cisco / ios_xe = 16.12.2a
cisco / ios_xe = 16.12.2s
cisco / ios_xe = 16.12.2t
cisco / ios_xe = 16.12.3
cisco / ios_xe = 16.12.3a
cisco / ios_xe = 16.12.3s
cisco / ios_xe = 16.12.4
cisco / ios_xe = 16.12.4a
cisco / ios_xe = 16.12.5
cisco / ios_xe = 16.12.5a
cisco / ios_xe = 16.12.5b
cisco / ios_xe = 17.1.1
cisco / ios_xe = 17.1.1a
cisco / ios_xe = 17.1.1s
cisco / ios_xe = 17.1.1t
cisco / ios_xe = 17.1.2
cisco / ios_xe = 17.1.3
cisco / ios_xe = 17.2.1
cisco / ios_xe = 17.2.1a
cisco / ios_xe = 17.2.1r
cisco / ios_xe = 17.2.1v
cisco / ios_xe = 17.2.2
cisco / ios_xe = 17.2.3
cisco / ios_xe = 17.3.1
cisco / ios_xe = 17.3.1a
cisco / ios_xe = 17.3.1w
cisco / ios_xe = 17.3.1x
cisco / ios_xe = 17.3.1z
cisco / ios_xe = 17.3.2
cisco / ios_xe = 17.3.2a
cisco / ios_xe = 17.3.3
cisco / ios_xe = 17.3.3a
cisco / ios_xe = 17.4.1
cisco / ios_xe = 17.4.1a
cisco / ios_xe = 17.4.1b
cisco / ios_xe = 17.4.1c

Frequently Asked Questions

A security vulnerability is a weakness in software, hardware, or configuration that can be exploited to compromise confidentiality, integrity, or availability. Many vulnerabilities are tracked as CVEs (Common Vulnerabilities and Exposures), which provide a standardized identifier so teams can coordinate patching, mitigation, and risk assessment across tools and vendors.

CVSS (Common Vulnerability Scoring System) estimates technical severity, but it doesn't automatically equal business risk. Prioritize using context like internet exposure, affected asset criticality, known exploitation (proof-of-concept or in-the-wild), and whether compensating controls exist. A "Medium" CVSS on an exposed, production system can be more urgent than a "Critical" on an isolated, non-production host.

A vulnerability is the underlying weakness. An exploit is the method or code used to take advantage of it. A zero-day is a vulnerability that is unknown to the vendor or has no publicly available fix when attackers begin using it. In practice, risk increases sharply when exploitation becomes reliable or widespread.

Recurring findings usually come from incomplete Asset Discovery, inconsistent patch management, inherited images, and configuration drift. In modern environments, you also need to watch the software supply chain: dependencies, containers, build pipelines, and third-party services can reintroduce the same weakness even after you patch a single host. Unknown or unmanaged assets (often called Shadow IT) are a common reason the same issues resurface.

Use a simple, repeatable triage model: focus first on externally exposed assets, high-value systems (identity, VPN, email, production), vulnerabilities with known exploits, and issues that enable remote code execution or privilege escalation. Then enforce patch SLAs and track progress using consistent metrics so remediation is steady, not reactive.

SynScan combines attack surface monitoring and continuous security auditing to keep your inventory current, flag high-impact vulnerabilities early, and help you turn raw findings into a practical remediation plan.